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		<title>three.js webgl - VSM Shadows example </title>
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		<div id="info">
		<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - VSM Shadows example by <a href="https://github.com/supereggbert">Paul Brunt</a>
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import Stats from 'three/addons/libs/stats.module.js';
			import { GUI } from 'three/addons/libs/lil-gui.module.min.js';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';

			let camera, scene, renderer, clock, stats;
			let dirLight, spotLight;
			let torusKnot, dirGroup;

			init();

			function init() {

				initScene();
				initMisc();

				// Init gui
				const gui = new GUI();

				const config = {
					spotlightRadius: 4,
					spotlightSamples: 8,
					dirlightRadius: 4,
					dirlightSamples: 8
				};

				const spotlightFolder = gui.addFolder( 'Spotlight' );
				spotlightFolder.add( config, 'spotlightRadius' ).name( 'radius' ).min( 0 ).max( 25 ).onChange( function ( value ) {

					spotLight.shadow.radius = value;

				} );

				spotlightFolder.add( config, 'spotlightSamples', 1, 25, 1 ).name( 'samples' ).onChange( function ( value ) {

					spotLight.shadow.blurSamples = value;

				} );
				spotlightFolder.open();

				const dirlightFolder = gui.addFolder( 'Directional Light' );
				dirlightFolder.add( config, 'dirlightRadius' ).name( 'radius' ).min( 0 ).max( 25 ).onChange( function ( value ) {

					dirLight.shadow.radius = value;

				} );

				dirlightFolder.add( config, 'dirlightSamples', 1, 25, 1 ).name( 'samples' ).onChange( function ( value ) {

					dirLight.shadow.blurSamples = value;

				} );
				dirlightFolder.open();

				document.body.appendChild( renderer.domElement );
				window.addEventListener( 'resize', onWindowResize );

			}

			function initScene() {

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 1000 );
				camera.position.set( 0, 10, 30 );

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0x222244 );
				scene.fog = new THREE.Fog( 0x222244, 50, 100 );

				// Lights

				scene.add( new THREE.AmbientLight( 0x444444 ) );

				spotLight = new THREE.SpotLight( 0xff8888, 400 );
				spotLight.angle = Math.PI / 5;
				spotLight.penumbra = 0.3;
				spotLight.position.set( 8, 10, 5 );
				spotLight.castShadow = true;
				spotLight.shadow.camera.near = 8;
				spotLight.shadow.camera.far = 200;
				spotLight.shadow.mapSize.width = 256;
				spotLight.shadow.mapSize.height = 256;
				spotLight.shadow.bias = - 0.002;
				spotLight.shadow.radius = 4;
				scene.add( spotLight );


				dirLight = new THREE.DirectionalLight( 0x8888ff, 3 );
				dirLight.position.set( 3, 12, 17 );
				dirLight.castShadow = true;
				dirLight.shadow.camera.near = 0.1;
				dirLight.shadow.camera.far = 500;
				dirLight.shadow.camera.right = 17;
				dirLight.shadow.camera.left = - 17;
				dirLight.shadow.camera.top	= 17;
				dirLight.shadow.camera.bottom = - 17;
				dirLight.shadow.mapSize.width = 512;
				dirLight.shadow.mapSize.height = 512;
				dirLight.shadow.radius = 4;
				dirLight.shadow.bias = - 0.0005;

				dirGroup = new THREE.Group();
				dirGroup.add( dirLight );
				scene.add( dirGroup );

				// Geometry

				const geometry = new THREE.TorusKnotGeometry( 25, 8, 75, 20 );
				const material = new THREE.MeshPhongMaterial( {
					color: 0x999999,
					shininess: 0,
					specular: 0x222222
				} );

				torusKnot = new THREE.Mesh( geometry, material );
				torusKnot.scale.multiplyScalar( 1 / 18 );
				torusKnot.position.y = 3;
				torusKnot.castShadow = true;
				torusKnot.receiveShadow = true;
				scene.add( torusKnot );

				const cylinderGeometry = new THREE.CylinderGeometry( 0.75, 0.75, 7, 32 );

				const pillar1 = new THREE.Mesh( cylinderGeometry, material );
				pillar1.position.set( 8, 3.5, 8 );
				pillar1.castShadow = true;
				pillar1.receiveShadow = true;

				const pillar2 = pillar1.clone();
				pillar2.position.set( 8, 3.5, - 8 );
				const pillar3 = pillar1.clone();
				pillar3.position.set( - 8, 3.5, 8 );
				const pillar4 = pillar1.clone();
				pillar4.position.set( - 8, 3.5, - 8 );

				scene.add( pillar1 );
				scene.add( pillar2 );
				scene.add( pillar3 );
				scene.add( pillar4 );

				const planeGeometry = new THREE.PlaneGeometry( 200, 200 );
				const planeMaterial = new THREE.MeshPhongMaterial( {
					color: 0x999999,
					shininess: 0,
					specular: 0x111111
				} );

				const ground = new THREE.Mesh( planeGeometry, planeMaterial );
				ground.rotation.x = - Math.PI / 2;
				ground.scale.multiplyScalar( 3 );
				ground.castShadow = true;
				ground.receiveShadow = true;
				scene.add( ground );

			}

			function initMisc() {

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				renderer.shadowMap.enabled = true;
				renderer.shadowMap.type = THREE.VSMShadowMap;

				// Mouse control
				const controls = new OrbitControls( camera, renderer.domElement );
				controls.target.set( 0, 2, 0 );
				controls.update();

				clock = new THREE.Clock();

				stats = new Stats();
				document.body.appendChild( stats.dom );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function animate( time ) {

				const delta = clock.getDelta();

				torusKnot.rotation.x += 0.25 * delta;
				torusKnot.rotation.y += 0.5 * delta;
				torusKnot.rotation.z += 1 * delta;

				dirGroup.rotation.y += 0.7 * delta;
				dirLight.position.z = 17 + Math.sin( time * 0.001 ) * 5;

				renderer.render( scene, camera );

				stats.update();

			}

		</script>
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